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By K. B. Chaudhuri, I. D. Webb, F. E. Rachor, F. A. Sauert

"A characteristic of all methods of copper concentrate smelting is that slags with a high copper content are produced at some phase of the operation. Recirculation to the smelting unit, electric furnace reduction or flotation are at present used on an industrial scale to recover the copper from these slags. This paper describes the application of the top-blowing technique, originally developed by KHD Humboldt- Wedag AG for refining of metallic copper, for the treatment of copper-containing slags. By this method, a mixture of a reducing gas and commercial oxygen is blown onto the melt at velocities which can be supersonic from the tip of a water cooled lance. The impingement of the reaction gas mixture on the surface of the slag forms a depression in the molten phase and a deflection of the jet which brings the slag into a rotating motion. This causes high rates of heat and mass transfer. Results of pilot-plant tests for batch and continuous treatment of slags are presented, and the potential applications of top blowing for industrial-scale operation are indicated. In combination with the cyclone as a smelting unit, this process appears to be economic for smelters of very low capacity."

Jan 1, 1980

By T. G. Carter

"Tremendous progress has been made in recent years towards developing computational tools that allow ready solution of most common rock engineering problems, with amongst the most advanced of the tools focusing on evaluating engineered openings within Synthetic Rock Masses. These new codes have the potential to allow much more realistic design, but they must not be used without careful calibration – prior to – during and – post completion of any modelling. This paper explores some of the pitfalls of inadequate data collection and suggests more emphasis be given to calibration. Guidelines for minimum levels of parameter data are suggested for improving application of basic to sophisticated modelling codes.INTRODUCTION & BACKGROUNDTremendous progress has been made in recent years towards developing computational tools that allow ready solution of most common rock engineering problems. The degree of sophistication now possible with some of the available codes allows one to tackle extremely complex problems that were not thought tractable even a decade ago. Indeed, generation of synthetic numerical rock masses, based on discrete fracture network representations that closely mimic actual rock mass conditions, such as are shown in Figure 1, is today relatively straightforward, and not as user-challenging as employing state-of-the-art codes of even a few decades ago. This is largely because major improvements in computer graphics and in availability of ready-made user-friendly input-output interfaces have paralleled development of these new codes, now in some cases outpacing actual new analytical/procedure developments. This is something of a reversal from the first few decades of DOS-based rock engineering computational experience, when only rudimentary graphics were available and user-friendly input-output interfaces were virtually non-existent."

Jan 1, 2015

By A. Makinen

There is an increasing trend between increasing consumption of water and the production of metal concentrate. Along with this trend we see that ore grades are declining and getting more complex to concentrate around the world. This will not only complicate processing but also generate new requirements for the management of water and waste streams on mining sites. The mining industry is a large user of water and its water consumption is growing rapidly. The processing of lower quality ores requires greater volumes of water. For these reasons, the need for efficient use of water and water management at mine sites is becoming more urgent. The perception of water in the mining industry has changed from thinking about it only in terms of "water treatment" to actually seeing it as a valuable resource, a resource that needs proper management. This resource management needs to involve various aspects, such as optimizing water usage of the entire mine or concentrator site, minimizing fresh water usage, minimizing or eliminating waste generated in water treatment and implementing practices for water reuse and water recycling. This paper presents trends and new developments relating to waste and water management in the mining industry.

Jan 1, 2015

By K. Huang

"Solvent extraction (SX) is one of the most effective techniques for the multi-metal separation. However, repetitive pre-treatment of feed-in solutions and/or multi-steps two phase equilibrating in conventional SX processes were always unavoidable due to the poor separation selectivity between those metals with similar physicochemical properties. In this paper, our recent efforts, aimed to develop a “Three Liquid Phase Extraction” (TLPE) strategy for one-step separation and selective enrichment of different metals respectively into three coexisted liquid phases, are reviewed. Various feasible “Three Liquid Phase Systems” (TLPS) are evaluated. The TLPE technique provides a potential possibility for multiphase extraction to separate multi-metals.INTRODUCTIONLiquid-liquid Solvent Extraction (SX) is one of the most effective techniques for metal separation and purification. Traditionally, extraction and separation of multiple valuable metals from the leaching solutions of complex ores, industrial wastes and byproducts have to face such difficulties that multiple target metals with similar physicochemical properties co-exist in the solutions, and therefore their mutual separation selectivities are very poor. In conventional organic-water two phase SX processes, repetitive pre-treatment of feed-in solutions including the adjustment of the solution acidity, removal of impurities and/or multi-step liquid-liquid two phase equilibration were always unavoidable (Wang and Chen, 2001). Only one of the target metals is obtained in each extraction step, therefore the whole separation processes for multi-metal separation are typically very long and costly.Liquid-liquid-liquid three phase extraction is a developing technique for separation of complex systems containing multiple target components (Tan, 2003; Shen, 2006; Yu, 2009). The technique is in fact a three-liquid-phase selectively partitioning of different target components through the control of phase-forming behaviors of extraction system to create a unique separation medium with three co-existed liquid phases. The separation selectivity of “Three-Liquid-Phase System” (TLPS) may derive from its three-layered liquid phases from up to down with different hydrophobic or hydrophilic environment, and therefore each phase has its own specific selectivity for dissolving of an individual component. In a well designed “Three-Liquid-Phase System” (TLPS), multiphase extraction and selective separation of different components respectively into three different liquid phases can be achieved by only one-step of extraction. Owing to its distinct advantages, “Three-Liquid-Phase Extraction” (TLPE) technique has found many potential applications in purification of various organic chemicals (Shen, 2007) and biological activities (Chen, 2002; Tan, 2006; Jiang, 2008), treatment of environmental wastewaters (Shen, 2006; Yu, 2009; Yu, 2010; He, 2012), extraction of valuable components in natural products (Liu, 2010) and separation of multi-metals in complex leaching solutions (Jin, 2009)."

Jan 1, 2012

By Peter Hayes, Evgueni Jak, Taufiq Hidayat, Gary O’Connell, Denis Shishin, Jeff Chen, Francis Letarte

"Knowledge of slag properties is required for the optimisation of smelting operations. The phase equilibria and viscosities of the Al2O3-CaO-FeO-Fe2O3-MgO-MnO-NiO-Cr2O3-SiO2 slags at conditions of interest to Koniambo Ni-laterite smelting operations have been investigated. High-temperature re-equilibration phase equilibrium experiments of industrial slags followed by rapid quenching and direct measurement of phase compositions using electron probe X-ray microanalysis (EPMA) have been undertaken in the olivine and pyroxene primary phase fields at temperatures between 1475 and 1600°C and SiO2/MgO weight ratios between 1.57 and 2.09. Phase equilibria predictions were performed using FactSage thermodynamic software. A slag viscosity model available in the FactSage thermodynamic package has been used to calculate the viscosities of the liquid slags. The Einstein-Roscoe equation combined with the predicted phase equilibria data have been used to estimate the viscosities of the slag slurries (slag + solids). The information provided can be used to assist in the evaluation of the furnace performance, to assess further optimisation of slag composition and to explore possibilities of targeted feed changes.INTRODUCTION One of the key steps in the production of ferronickel from nickel laterite ore at Koniambo Nickel SAS involves reduction and smelting of pre-dried nickel-bearing saprolitic ore (high Mg and Si) in an electric furnace at temperatures up to 1650°C. The characterisation of the slag properties as functions of key operational parameters, such as, temperature and composition, including liquidus, the proportions of solids and viscosity, is essential for improving control and optimisation of the operations. The slag produced in the smelting process is a complex oxide system with the major chemical components including Al2O3, CaO, Cr2O3, “FeO”, MgO, “MnO”, “NiO” and SiO2. Characterisation of these multi-component systems using a solely experimental approach becomes increasingly complex as the number of components is increased."

Jan 1, 2017

By W G. Brese

The attention of the world is being focused on the spectacular rise of elemental sulphur production in Alberta. In the short space of a decade, production has increased from less than 10,000 long tons, in 1952, to al-most 1,000,000 long tons in 1962. Moreover, 1963 sulphur production is expected to rise by 50 per cent to approximately 1,500,000 long tons, and further increases are forecast for ensuing years. The reason for this dramatic in-crease in elemental sulphur production, particularly in the last year or two, is that Alberta elemental sulphur is recovered in association with the production of sour natural gas. When very large volumes of natural gas began moving to U.S. markets in the latter part of 1961, the resultant increase in sour gas production led to a marked increase in the production of sulphur. Consequently, Canada, mainly on the strength of sulphur produced in Alberta, will soon become the second largest producer of sulphur in the Free World

Jan 1, 1963

By D. R. E. Whitmore, J. M. Harrison

There are five logical stages in the search for orebodies in virgin territory, namely: (1) reconnaissance inventory of geology, and related investigations; (2) development of broad concepts as a basis for selecting regions of potential mineral deposits; (3) assessment of criteria leading to specific localities within these regions; (4) geo-physical and geochemical studies that will delineate small anomalous areas; and (5) stripping, drilling or other means of locating ore. In addition, the development of new means of extracting mineral resources and the finding of new uses play a vital role in our mineral industry. The continued growth of this industry will be largely governed by our ability to develop or to adapt new concepts and techniques, and to produce a greater number of scientists and engineers. It should always be remembered that more than one-third of Canada's exports are dependent upon our ability to find, develop and economic-ally exploit new orebodies.

Jan 1, 1967

By Jozef S. Stachula

"INCO Limited operates eleven under-ground mines in the Sudbury area. The mines are located on the rim of the Sudbury Basin, an oval with the axis in the range of 27 km and 60 km. The ore dips to at least 3000 m below surface. The ores are mined primarily for nickel and copper. Total ore production from underground is in excess of 55 000tonnes per day.Over 40 surface fans have been installed since the late 1960s. All of the fans are adjustable pitch, axial flow units. A major factor influencing ventilation design in the last 30years has been the introduction of diesel equipment underground. Volumes per fan have ranged from 60 m3/sec. to 330 m3/sec., with motors from 100 hp to 2500 hp.Fans of the axial flow type have been commonly used for main fan installations at Canadian mines for many years. The standard arrangement has been to mount these fans horizontally, i.e. with the fan shaft and the long axis of the housing horizontal. This is a natural arrangement for an underground fan, but for a surface installation, a vertically mounted fan has definite advantages.The surface area taken up by a typical vertical fan installation is generally about one quarter that of a horizontal fan of the same capacity (Rutherford, 1957). This is not a problem with isolated fans and fat surface out crop sites, but where the installation is to be near existing buildings, or where there are poor surface soil conditions, space and cost considerations greatly flavour vertical fans."

Jan 1, 1996

By P. H. Tolcher

Canada, as the Free World's largest mine producer of zinc and the third largest mine producer of lead, has a vital interest in the future growth in demand for these metals. This paper traces the development of lead and zinc consumption in the last two decades, both on a total-Free-World basis and by major market areas. How Canada, as a major mine producer, has shared in this growth is also indicated. In addition, future consumption for both metals in the current decade of the 1970's is fore-cast. The demand these projections will make on Free World mines, particularly on Canadian mines, is examined. Some of the opportunities and challenges the Canadian mining industry will likely face during this period are also dealt with.

Jan 1, 1971

By C. Allen

In 2004, Boliden Odda underwent an extensive modernisation project targeting mainly the leaching section of the plant. Direct leach technology was introduced as part of this project. The Direct Leach process, developed by Outokumpu, is an atmospheric oxidative leach of zinc sulphide concentrate. The effects of this new processing operation on behaviour of iron in the plant are discussed. As well, the filterability of the new residue on belt filters prior to its deposition in mountain caverns is also discussed. The solids from the direct leach process have been analysed by scanning electron microscopy, and the results of these analyses are presented.

Jan 1, 2006

By H. Feldheiser

Acid resistant brick linings are state of the art for anti-corrosion linings in tanks for high pressure acid leaching (HPAL) treatment. The design of these brick linings has to take into account the almost non-elastic behaviour of the brick lining inside a relatively highly elastic steel vessel. There must be tools and data available to determine for the steel vessels the thermal growth plus the pressure expansion and for the brick lining the linear thermal expansion and the chemical swell. Thermal shocks and pressure drops are not regular operating events but their negative influence on the lifetime of a brick lining has to be a part of the engineering study. Finite Element (FE) models as well as a lot of research and development on brick lining materials is the only way to find a path through the complex engineering work for pressure vessels.

Jan 1, 2004

Between 1993 and 2003, a series of AG and SAG mill pilot plant trials were conducted using Hardinge Ical pilot plant scale SAG mills on numerous ore samples and ranging across a wide variety of operating conditions. The data from these tests were used to evaluate the design of SAG and AG mill circuits for over a dozen projects, of which about half were eventually constructed and commissioned. The data were also used in the development of SAG mill modelling, scale-up and simulation procedures by several consultants who had access to part of the data set. Recently, we have had the opportunity to bring this data together and further analyse the consolidated dataset. This paper reports on the outcomes of this analysis that has identified the impacts of different AG/SAG circuit flowsheets and operating conditions on energy efficiency and operating cost.

Jan 1, 2012

By N. Manopulo, J. Maier, L. Tong, C. Becker, P. Hora

The contribution presents a new finite element approach in which the common updated Lagrangian formulation is replaced by a spatial flow formulation applying a special arbitrary Lagrangian-Eulerian for-mulation (ALE). The description separates spatially the process in a die inside zone and in a profile zone. For the description of the inside zone, where the filling process occurs, a special Euler time independent mesh is applied. By this formulation the mesh has to be generated only once, which simplifies the generation of spatially optimized meshes. For mapping of the material flow during the filling process the method uses a flow surface traction method as applied in casting simulations. A further strength of the new method is the computational efficiency which allows the modelling of extrusion process with the highest complexity with a response time of 12 hours, which is important for the industrial optimization process.

Jan 1, 2015

By G. Goodall, M. Muinonen, R. Pandher, R. Jabbar, S. J. Muinonen

"The implementation of a new and highly efficient converting practice at the Glencore Sudbury Integrated Nickel Operations Smelter has opened the possibility to further capacity increases by using larger ladles. To quantify the impact of increasing ladle sizes from 200 to 300 ft3, XPS constructed a detailed discrete event simulation using the commercial software package Rockwell Arena®. The challenges associated with implementing a model on an intricate and tightly scheduled process, and the solutions needed to derive meaningful results will be presented. The aisle capacity is predicted to increase by approximately 17 %, with a reduction in furnace tapping demand of 8 %. Arena modeling capabilities and the key factors contributing to the overall capacity increase at the Sudbury INO Smelter will be reviewed and presented.INTRODUCTION The Glencore Sudbury Integrated Nickel Operations (INO) comprises two Ni-Cu-PGM mines, Strathcona Mill, and the Sudbury Smelter. The Smelter has operated continuously since 1929 using different processes to produce nickel-copper Bessemer matte. Feeds to the Sudbury INO Smelter are a blend of concentrate from Strathcona Mill, Raglan concentrate produced at the mine-mill complex in Raglan, Quebec, as well as third party concentrate feeds shipped to Sudbury from around the world. In 2016, the Sudbury INO Smelter produced 75,900 tonnes of nickel and 20,000 tonnes of copper in Bessemer matte. The product matte is shipped to Glencore’s Nikkelverk refinery in Kristiansand, Norway where it is refined to produce nickel and copper cathode. A schematic of the Sudbury INO Smelter’s flowsheet is shown in Figure 1."

Jan 1, 2017

By R. L. Bruening, R. M. Izatt, N. E. Izatt, S. R. Izatt

"Molecular Recognition Technology (MRT) is a simplified, green chemistry process with applications in selective separations of Ni(II), Co(II), and platinum group metals in primary ore beneficiation processes and secondary recovery operations from spent products, scrap, and environmental waste solutions. Simplification in MRT processes is achieved by non-use of solvents, reduced space requirements, and a simple separation system involving columns packed with metal-selective SuperLig® resins. Minimal waste is generated and metal recovery is achieved at 99% levels from g L-1 to <mg L-1 concentrations. MRT systems are attractive technologically and economically compared with solvent extraction, ion exchange, and precipitation separation processes. Commercial examples of MRT use include removal of impurity metals Cd, Cu, Ni. Fe, and Pb to mg L-1 or lower concentration levels from Co streams to produce battery-grade Co. Highly purified Co is required for optimal function of lithium ion rechargeable batteries and superalloys associated with aerospace and gas turbine operations. Impurity metals are recovered for reuse or proper disposal rather than being discarded to landfill. Green chemistry processes, such as MRT, are needed in metal separations going forward into the 21st century to achieve global metal sustainability in processing of native ore and treatment of secondary sources.INTRODUCTION Maximizing efficiencies of metal separations and optimizing metal recovery rates during separation processes are important goals on the road to achieving metal sustainability. Achievement of these goals is consistent with stated principles of green engineering (O'Connor, Zimmerman, Anastas, & Plata, 2016) and green chemistry (Anastas & Eghbali, 2010). Molecular Recognition Technology (MRT) separation processes using SuperLig® resins have a 25-year record of performing competitive, commercial metal separations with metal recovery rates approaching 100% (Izatt, Izatt, Izatt, Krakowiak, & Bruening, 2017). SuperLig® resins are characterized by high selectivities for specific metals over concentration ranges from g L-1 to mg L-1 or lower. MRT systems use no solvents and are simple in design and operation resulting in reduced capital and operating expenses."

Jan 1, 2017

By J. Olson

"A model was developed to use near-infrared (NIR) analysis of pulverized ore samples to estimate the recoverable gold content for ores from the Barrick Cortez Hills underground mine. Current routing practices use a ratio of the cyanide soluble gold content and fire assayed gold (CN/FA) to classify ores as oxide or refractory. Prediction accuracy of the NIR model was equivalent to the CN/FA ratio. Prediction accuracy was improved by combining the CN/FA ratio and the NIR spectra. Bootstrap validation estimates the root-mean-square error to be 9.92% with an estimated r-squared value of 0.893. This model will allow more accurate estimates of the variability in recoverable gold content throughout this mine. These data will aid in building an improved geo-metallurgical model or in making better informed routing decisions during the production cycle.INTRODUCTION The contained gold of an ore available for cyanidation is often related to subtle variations in the mineralogy. It is difficult and expensive to collect enough mineralogical information in order to predict how the variable mineralogy will impact the metallurgical results and project economics throughout the life of the mine or mill. Near-infrared spectroscopy may be an effective tool to rapidly and inexpensively collect discrete, quantitative mineralogical data for minerals that contain transition metal oxides, metal sulfides with semi-conduction properties, rare earth metals, and some chemical groups having di-pole covalent bonds such as carbonates, sulfates, and various types of clays (Hunt, 1977). Near-infrared spectroscopy can be a powerful tool for geo-metallurgical characterization of deposits where the presence of these minerals has direct or indirect relationships to metallurgical results such as grindability, regent consumption, or recovery. Near infrared spectroscopy is a rapid analysis that measures the intensity of reflected light in the near-infrared spectrum. The ranges for the ASD-Panalytical units used in this study extend through the visible spectrum and into part of the UV spectrum, reporting reflection by wavelength from between 350 nm to 2500 nm. Absorption peaks visible in this range are a result of interactions with outer valence elections or chemical bonds. The location and intensity of the peaks vary depending on the chemical composition and crystal structure of a solid indicating the presence and abundance certain minerals (Hunt, 1977; Clark, 1984)."

Jan 1, 2017

By Jirí Faltus

The paper deals with studying the impact of structural properties and anodizing of surface on the corrosion properties of extruded rods from commercial aluminium alloys: AA6082, AA6262, AA6012, AA2007 and new lead-free aluminium alloys AA6023, AA2015 and AA2111B. Samples were exposed to the corrosive atmosphere NSS, AASS in the chamber by EN ISO 9227. Surface of samples were either in the original state or anodizing by selected mode. The depth of corrosion attack and the form of corrosion attack are evaluated depending on the type of alloy, the metallurgical condition and surface treatment of the samples.

Jan 1, 2015

By D. Ofstie, B. Kargutkar

BIM, or Building Information Modeling, is transforming the way metallurgical facilities are built, operated and maintained. BIM provides a digital representation of the facility, complete with all physical and functional characteristics - enabling collaborative planning, concurrent design, construction simulation, sustainable operations and predictive maintenance through a connected information model. Building on experience gained in other industries, Hatch is aggressively applying the BIM process to the mining & minerals processing industry to address inefficiencies inherent in traditional document-based information management. Intelligent 3D models support real-time quantity forecasting and cost trending by commodity type and construction work package. By linking procurement and schedule data, material availability and constructability reviews are visualized to verify construction critical path, ensure work front safety and minimize craft downtime. The BIM digital information model connects engineering, construction, commissioning and vendor data, aiding timely asset-centric handover to plant operating and maintenance systems.

Jan 1, 2015

By Hao Zhang

Site inspection is an important component of safety management system. In current practices, the inspectors evaluate the safety condition on a construction site with the assistance of a standardised checklist. However, the checklist emphasizes on evaluating the implementation of safety management system, but provides limited task-specific check items for assessing whether the individual construction tasks are conducted under safe condition and in a safe manner. To address this issue, the research presented in this paper aims to provide safety practitioners with comprehensive and taskspecific safety information to promote effective risk identification and facilitate strategic risk control during site inspection. Specifically, this research first builds a project-specific safety information database, which stores potential risks and control measures for each construction task. The research team then develops a mobile decision support tool to retrieve information from the database and support safer decision-making on site. The tool supports users in two ways: one is to provide daily risk checklists and risk control strategies to guide step-by-step inspection alongside the project schedule; the other is to let users input any safety-related keywords during the safety inspection process and the tool returns relevant safety information by applying text mining algorithms. It is ongoing research. This paper presents an overall research framework and discusses the progress in developing safety database and data retrieval concepts. The outcome of the project will help enhance safety management practices and reduce possible risky working conditions on a construction site.

Aug 1, 2013

By A. M. L. Cushing, S. Kelebek

Presently, adsorption is one of the effective methods of removing toxic contaminants from waste waters. The contaminants from metal mining industrial operations include an effluent water containing various types of heavy metal species at concentrations beyond the maximum allowable limits, which are 0.5 ppm and 0.3 ppm for nickel and copper species, respectively. Adsorption behavior of copper ions pre-chelated with diethylenetriamine (DETA) and triethylenetetramine (TETA) onto natural bentonite and peat has been investigated. Both natural bentonite and peat was found to be capable of removing these copper-polyamine complexes from aqueous solutions relevant to process water effluents. However, the adsorption capacity of bentonite was significantly higher than that of peat. Two models were used to study the adsorption kinetics: a pseudo-first-order rate expression and a pseudo-second-order rate expression. For both adsorbents, the data conformed best to the pseudo-second-order rate expression. Representation of the experimental data through adsorption models was also investigated. Out of the four cases considered, namely, Langmuir, Freundlich, Temkin and Dubinin-Radushkevich isotherms, it was found that for both bentonite and peat, the copper polyamine adsorption data conformed best to the Dubinin-Radushkevich adsorption model. The Langmuir model also represents the bentonite-copper polyamine adsorption system reasonably well as the second best case, suggesting that the amount adsorbed on bentonite might be a monolayer with strong affinity.

Jan 1, 2015